Some people have iron self discipline--they simply make a decision, or will themselves to something, and if it lies within their power in any way, it gets done,

Some people have iron self discipline--they simply make a decision, or will themselves to something, and if it lies within their power in any way, it gets done, end of story. I sort of did myself in my mid 20s for a few years, but I can't really explain it. I'd sort of like to see the psychology of that. Even having experienced it, I still can't entirely explain it. (I used to meditate for 2 hours a day in that time period, but ...cause or effect? I don't know.)